Rollable display device

ABSTRACT

A rollable display device is disclosed. The rollable display device includes a display panel, a driving unit including a motion converting unit configured to linearly move in a width direction of the display panel in conjunction with a rotational motion of a motor, a lifting unit connected to one end of the display panel and the motion converting unit, and configured to move up and down the display panel in a longitudinal direction of the display panel in conjunction with a linear motion of the motion converting unit, and a panel roller unit connected to other end of the display panel, and configured to roll and unroll the display panel along a periphery of the panel roller unit in conjunction with moving up and down of the display panel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/794,288 filed on Oct. 26, 2017, which claims the priority benefit ofKorean Patent Application No. 10-2016-0140353 filed on Oct. 26, 2016,all of which are hereby incorporated by reference in their entirety asif fully set forth herein.

BACKGROUND Field of the Disclosure

The present disclosure relates to a display device, and moreparticularly, to a rollable display device.

Description of the Background

With the advancement of information technologies, the demands fordisplay devices which enable a user to access information haveincreased. Accordingly, various types of the display devices are widelyused, such as an electroluminescent display, a liquid crystal display(LCD), and a plasma display panel (PDP).

Since the electroluminescent display is a self-light emitting device,power consumption is lower than that of a liquid crystal display devicerequiring a backlight, and the electroluminescent display can be madethinner than the liquid crystal display device. In addition, theelectroluminescent display has a wide viewing angle and a high responsespeed. The electroluminescent display is expanding the market whilecompeting with the liquid crystal display device by developing processtechnology up to the level of large-screen mass production technology.

Pixels of the electroluminescent display include organic light emittingdiodes (OLEDs) which are self light emitting elements. Theelectroluminescent display may be divided depending on kinds of lightemitting materials, light emitting methods, light emitting structures,driving methods, and the like. Accordingly, the electroluminescentdisplay may be divided into a fluorescent emission and a phosphorescentemission depending on a light emitting method and may be divided into atop emission structure and a bottom emission structure depending on alight emitting structure. In addition, the electroluminescent displaymay be divided into a passive matrix OLED (PMOLED) and an active matrixOLED (AMOLED) depending on a driving method.

Recently, a flexible display device has been commercialized. Theflexible display device can reproduce input images on a screen of adisplay panel on which a plastic OLED is formed. The plastic OLED isformed on a flexible plastic substrate. The flexible display device canbe implemented in various designs, and has advantages in portability anddurability. The flexible display device can be implemented in variousforms such as a bendable display device, a foldable display device, anda rollable display device. Such a flexible display device can be appliednot only to a mobile device such as a smart phone and a tablet PC butalso to a television (TV), an automobile display, and a wearable device,and the application field thereof is expanding.

A display panel of the rollable display device can be rolled or unrolledas needed. When a user desires to use the rollable display device, thedisplay panel needs to be kept unrolled. Since a conventional rollabledisplay device does not include a fixture for holding the display panelin the unrolled state, unlike the user's desire, the display panel canreturn to be the rolled state during the using. The absence of thefixture can degrade usability of the user and is problematic.

SUMMARY

Accordingly, the present disclosure is to provide a rollable displaydevice including a structure capable of facilitating an operation ofrolling and unrolling a display panel and capable of supporting thedisplay panel.

In one aspect, a rollable display device comprises a display panel; adriving unit including a motion converting unit configured to linearlymove in a width direction of the display panel in conjunction with arotational motion of a motor; a lifting unit connected to one end of thedisplay panel and the motion converting unit, and configured to move upand down the display panel in a longitudinal direction of the displaypanel in conjunction with a linear motion of the motion converting unit;and a panel roller unit connected to other end of the display panel,wherein the display panel is unrolled and rolled along a periphery ofthe panel roller unit corresponding to moving up and down of the displaypanel.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure and are incorporated in and constitute apart of this application, illustrate aspects of the disclosure andtogether with the description serve to explain the principles of thedisclosure.

In the drawings:

FIG. 1 is a schematic view of a rollable display device according to anaspect of the present disclosure;

FIG. 2 is a schematic view of a pixel shown in FIG. 1;

FIG. 3 is a view illustrating a structure of a modular display panel;

FIGS. 4A and 4B are views illustrating an example of use of a rollabledisplay device according to an aspect of the disclosure;

FIG. 5 is a perspective view illustrating a rollable display deviceaccording to an aspect of the disclosure;

FIGS. 6A and 6B are perspective views illustrating an operation state ofa rollable display device according to an aspect of the presentdisclosure;

FIG. 7 is a view illustrating a driving unit of a support assembly;

FIGS. 8A and 8B are views respectively illustrating a structure and anoperation state of a motion converting unit;

FIG. 9 is a view illustrating a lifting unit of a support assembly;

FIGS. 10A, 10B and 11 are views illustrating a structure and anoperation state of a motion converting unit;

FIG. 12 is a view illustrating an example of driving of a driving unit;

FIGS. 13A and 13B are views illustrating a rollable display deviceaccording to another aspect of the present disclosure; and

FIGS. 14A and 14B are views illustrating a rollable display deviceaccording to still another aspect of the disclosure.

DETAILED DESCRIPTION OF THE ASPECTS

Reference will now be made in detail to aspects of the disclosure,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts. It will be paid attentionthat detailed description of known arts will be omitted if it isdetermined that the arts can mislead the aspects of the disclosure. Indescribing various aspects, the same components may be described at theoutset and may be omitted in other aspects.

The terms “first”, “second”, etc. may be used to describe variouscomponents, but the components are not limited by the terms. The termsare used only for the purpose of distinguishing one component from othercomponents.

A display device according to an aspect of the disclosure may beimplemented based on a display device such as a liquid crystal display(LCD), a field emission display (FED), a plasma display panel (PDP), anelectroluminescent display, an electrophoresis display (EPD), a quantumdot display (QDD), or the like. Hereinafter, for convenience ofexplanation, a rollable display device including an organic lightemitting diode (hereinafter, referred to as OLED) will be described asan example.

FIG. 1 is a schematic view of a rollable display device according to anaspect of the disclosure. FIG. 2 is a schematic view of a pixel shown inFIG. 1. FIG. 3 is a view illustrating a structure of a modular displaypanel.

Referring to FIG. 1, a rollable display device 10 according to an aspectof the disclosure includes a display driving circuit and a display panel100.

The display driving circuit includes a data driver 12, a gate driver 14,and a timing controller 16, and writes a video data voltage of an inputimage to pixels of the display panel 100. The data driver 12 convertsdigital video data RGB input from the timing controller 16 into ananalog gamma compensation voltage to generate a data voltage. The datavoltage output from the data driver 12 is supplied to data lines D1 toDm. The gate driver 14 sequentially supplies a gate signal synchronizedwith the data voltage to gate lines G1 to Gn to select the pixels of thedisplay panel 100 to which the data voltage is written.

The timing controller 16 receives a timing signal such as a verticalsynchronizing signal Vsync, a horizontal synchronizing signal Hsync, adata enable signal DE and a main clock MCLK, and the like input from ahost system 19, and synchronizes operation timing of the data driver 12and the gate driver 14. Data timing control signal for controlling thedata driver 12 includes a source sampling clock SSC, a source outputenable signal SOE, and the like. Gate timing control signal forcontrolling the gate driver 14 includes a gate start pulse GSP, a gateshift clock GSC, a gate output enable signal GOE, and the like.

The host system 19 may be implemented as one of a television system, aset-top box, a navigation system, a DVD player, a Blu-ray player, apersonal computer (PC), a home theater system, and a phone system. Thehost system 19 includes a system on chip (SoC) with an embedded scalerto convert the digital video data RGB of the input image into a formatsuitable for displaying on the display panel 100. The host system 19transmits the timing signals Vsync, Hsync, DE, and MCLK together withthe digital video data RGB to the timing controller 16.

A pixel array of the display panel 100 includes pixels defined by thedata lines (D1 to Dm, where m is a positive integer) and the gate lines(G1 to Gn, where n is a positive integer). Each of the pixels includesan OLED which is a self-light emitting element.

Referring further to FIG. 2, in the display panel 100, a plurality ofdata lines D and a plurality of gate lines G intersect, and pixels arearranged in a matrix form in each of the intersecting regions. Each ofthe pixels includes an OLED, a driving thin film transistor(hereinafter, referred to as TFT) DT for controlling an amount ofcurrent flowing through the OLED, and a programming unit SC for settinga gate-source voltage of the driving TFT DT.

The programming unit SC may include at least one switching TFT and atleast one storage capacitor. The switching TFT is turned on in responseto a gate signal from the gate line G to apply a data voltage from thedata line D to one electrode of the storage capacitor. The driving TFTDT controls the amount of current supplied to the OLED depending on amagnitude of a voltage charged in the storage capacitor to control anamount of light emitted from the OLED. The amount of light emitted fromthe OLED is proportional to the amount of current supplied from thedriving TFT DT. Each of the pixels is connected to a high potentialpower source EVDD and a low potential power source EVSS, and aresupplied with a high potential power supply voltage and a low potentialpower supply voltage from a power generator (not shown). TFTsconstituting a pixel may be implemented as a p-type or an n-type. Inaddition, a semiconductor layer of the TFTs constituting the pixel mayinclude amorphous silicon, polysilicon, or an oxide. The OLED includesan anode electrode ANO, a cathode electrode CAT, and an organic compoundlayer interposed between the anode electrode ANO and the cathodeelectrode CAT. The anode electrode ANO is connected to the driving TFTDT.

Referring further to FIG. 3, the display panel 100 is electricallyconnected to the timing controller 16 shown in FIG. 1, the data driver12, the gate driver 14, and the like (the host system 19 shown in FIG. 1and the power generator not shown), and is modularized.

The gate driver 14 may be formed on the display panel 100 by a gate inpanel (GIP) manner. That is, the gate driver 14 may be formed in a GIPmanner on left, right, or both left and right sides of a display areaAA, so that the display panel 100 can be easily rolled and unrolled.However, the aspect of the disclosure is not limited thereto.

A data printed circuit board (PCB) 20 is electrically connected to thedisplay panel 100 through a first connection member 25. The firstconnection member 25 may be a chip on film (COF) on which the datadriver 12 is mounted, but is not limited thereto. For example, the firstconnection member 25 may be implemented by a tape carrier package (TCP)manner to electrically connect the data PCB 20 and the display panel100.

The data PCB 20 is connected to a control board 30 through a secondconnection member 35. The second connection members 35 may be plural.The timing controller 16 and the like are mounted on the control board30. The second connection member 35 may be a flexible flat cable (FFC),but is not limited thereto. The control board 30 may be connected to thehost system 19 shown in FIG. 1, the power generator, and the likethrough a connection cable.

FIGS. 4A and 4B are views illustrating an example of use of a rollabledisplay device according to an aspect of the disclosure.

Referring to FIGS. 4A and 4B, a display panel 100 includes a displayarea in which an input image is reproduced. A user can recognizeinformation output from the display panel 100 through the display area.A front surface of the display panel 100 refers to one surface of thedisplay panel 100 in which the display area is defined. Conversely, aback surface of the display panel 100 refers to one surface of thedisplay panel 100, in a direction opposite to the front surface thereof,in which the user can not recognize the display area. However, thepresent disclosure is not limited thereto. If necessary, the displayarea can also be defined on the back surface of the display panel 100.

The display panel 100 may be rolled and unrolled. That is, the displaypanel 100 may be easily and repeatedly subjected to rolling (or winding)operations or unrolling (or unwinding) operations by being given apredetermined flexibility. As shown in FIG. 4B, the display panel 100may be rolled (Inner rolling) in a front surface direction of thedisplay panel 100 and may be rolled (Outer rolling) in a back surfacedirection of the display panel 100. Hereinafter, for convenience ofexplanation, an instance of that the display panel 100 is rolled in theback surface direction will be described as an example, unless otherwisespecified.

Hereinafter, referring to FIGS. 5 to 12, a rollable display deviceaccording to a first aspect of the disclosure will be described. FIG. 5is a perspective view illustrating a rollable display device accordingto an aspect of the disclosure. FIGS. 6A and 6B are perspective viewsillustrating an operation state of a rollable display device accordingto an aspect of the disclosure. FIG. 7 is a view illustrating a drivingunit of a support assembly. FIGS. 8A and 8B are views illustrating astructure and an operation state of a motion converting unit. FIG. 9 isa view illustrating a lifting unit of a support assembly. FIGS. 10A, 10Band 11 are views illustrating a structure and an operation state of amotion converting unit. FIG. 12 is a view illustrating an example ofdriving of a driving unit.

Referring to FIGS. 5, 6A and 6B, the rollable display device accordingto an aspect of the disclosure includes a display panel 100, a supportassembly 200, and a panel roller unit 300.

The display panel 100 may have a square or rectangular planar shape, butis not limited thereto. For example, the planar shape of the displaypanel 100 may be irregular shape (or a free form shape) including acircle.

Hereinafter, a width direction (for example, an x-axis direction) of thedisplay panel 100 is defined as a first direction, a longitudinaldirection (for example, a y-axis direction) of the display panel 100 isdefined as a second direction, and a thickness direction (for example, az-axis direction) of the display panel 100 is defined as a thirddirection.

The display panel 100 can be rolled or unrolled, and can maintain afirst state ST1 and a second state ST2 as shown in FIGS. 6A and 6B. Thedisplay panel 100 may be changed from the first state ST1 to the secondstate ST2 or from the second state ST2 to the first state ST1 asnecessary. The first state ST1 indicates a state in which the displaypanel 100 is rolled. Since a display area of the display panel 100 isnot exposed to outside in the first state ST1, the first state ST1 maybe a state in which a user can not recognize the display area fromoutside. In the first state ST1, the rollable display device may beturned off so that no input image is displayed.

The second state ST2 indicates a state in which the display panel 100 isunrolled. In the second state ST2, the display panel 100 can maintain asubstantially flat shape. The second state ST2 may be a state in whichthe user can recognize the display area of the display panel 100 fromoutside and be provided with necessary information. In the second stateST2, the rollable display device may be turned on so that the inputimage is displayed.

Although not shown, a back cover may be further provided on a backsurface of the display panel 100. The back cover supports the backsurface of the display panel 100 and reinforces rigidity of the displaypanel 100. That is, an aspect of the disclosure can improve physicaldurability of the display panel 100 by further including the back cover.The back cover may include a lightweight and high-strength material. Forexample, the back cover may be formed of one of glass fiber reinforcedplastics (GFRP), carbon fiber reinforced plastics (CFRP), aluminum, andplastic.

The support assembly 200 includes a driving unit 250 and a lifting unit270. An aspect of the disclosure can support the unrolled display panel100 on the back surface of display panel 100 and maintain a flat stateof display panel 100 by having the support assembly 200. Thus, there isan advantage that usability of the rollable display device can beimproved.

Referring to FIGS. 7, 8A and 8B, the driving unit 250 includes a motor210 and a motion converting unit 230. The motor 210 may be fixed at apredetermined position of a base member 510. The motor 210 is connectedto a power generator such as an external power source or an embeddedbattery and can receive power. The motor 210 generates a rotationalforce to provide a driving force (i.e., rotational force) to the motionconverting unit 230.

The motion converting unit 230 is connected to the motor 210 and isconfigured to convert a rotational motion of the motor 210 into a linearreciprocating motion in the first direction. For example, the motionconverting unit 230 may be implemented as a shaft (or a screw) 231 and aball screw including a nut (or a ball nut) 235 which is coupled to theshaft 231.

The shaft 231 receives the rotational force from the motor 210 andperforms a rotational motion with reference to a rotation axis extendingalong the first direction. The nut 235 coupled to the shaft 231 performsa linear reciprocating motion corresponding to a rotation direction ofthe shaft 231.

One end of the shaft 231 is coupled to be rotatable to a shaft bracket401 fixed on the base member 510. Therefore, the movement of the shaft231 other than the rotational motion with respect to the rotation axiscan be restricted. That is, the shaft 231 has a degree of freedom in therotation direction with respect to the rotation axis. A bearing may befurther provided between the shaft bracket 401 and the shaft 231 so thatthe rotational motion of the shaft 231 can be facilitated. The movementof the nut 235 other than the linear reciprocating motion in the firstdirection can be restricted. That is, the nut 235 has a degree offreedom in the first direction.

For example, as shown in FIGS. 8A and 8B, when the shaft 231 rotates ina forward direction ({circle around (1)}), the nut 235 can be linearlymoved in +x-axis direction ({circle around (2)}). When the shaft 231rotates in a reverse direction ({circle around (1)}′), the nut 235 canbe linearly moved in −x-axis direction ({circle around (2)}′). Thedirection of linear motion of the nut 235 corresponding to the rotationdirection of the shaft 231 can be determined depending on a direction inwhich a screw groove between the shaft 231 and the nut 235 is formed.

A limit sensor 630 (shown in FIG. 5) capable of restricting the movementof the nut 235 may be further provided on the base member 510. The limitsensor 630 is provided at a predetermined position and may restrict themovement of the nut 235 so that the nut 235 can move only within apredetermined interval. For example, a controller can control on/off ofthe motor 210 through a signal sensed through the limit sensor 630.

Referring to FIGS. 9 to 12, the lifting unit 270 is configured to moveup and down the display panel 100 in conjunction with the linear motionof the motion converting unit 230. The lifting unit 270 is formed in alink structure and can repeatedly perform a folding or an unfoldingoperation by receiving a driving force from the motion converting unit230. When the display panel 100 is in the first state ST1, the liftingunit 270 maintains a folded state. In other words, when the displaypanel 100 is in the first state ST1, the lifting unit 270 has a lowestheight. When the display panel 100 is in the second state ST2, thelifting unit 270 maintains an unfolded state. In other words, when thedisplay panel 100 is in the second state ST2, the lifting unit 270 has ahighest height.

The lifting unit 270 may be implemented as a scissor lift structure.That is, the lifting unit 270 includes a link portion LP. The linkportion LP includes a first link LN1 and a second link LN2. The firstlink LN1 and the second link LN2 intersect with each other to havescissor shape (or an ‘X’ shape) and are coupled to be rotatable via afirst hinge HG1.

For example, the lifting unit 270 may include a first link portion LP1and a second link portion LP2 arranged along a second direction. Thefirst link portion LP1 includes a 1-1 link LN1-1 and a 1-2 link LN1-2.The 1-1 LN1-1 and the 1-2 link LN1-2 of the first link portion LP1intersect with each other in a scissor shape and are coupled to berotatable via a 1-1 hinge HG1-1.

One end of the 1-1 link LN1-1 is coupled to be rotatable to a hingebracket 405 fixed on the base member 510. The 1-1 link LN1-1 has adegree of freedom in a rotation direction with respect to a rotationaxis extending along the third direction. As shown in the figure, thehinge bracket 405 and the shaft bracket 401 may be formed as one body,but the aspect of the disclosure is not limited thereto.

One end of the 1-2 link LN1-2 is provided so as to be movable inconjunction with the linear motion of the motion converting unit 230.That is, the one end of the 1-2 link LN1-2 may be coupled to berotatable to the nut 235 of the ball screw. Accordingly, the 1-2 linkLN1-2 is rotatable with respect to a rotation axis extending along thethird direction and is provided to be capable of linear reciprocatingmotion corresponding to the linear reciprocating motion of the nut 235.A rotational motion of the nut 235 can be limited by a coupled structurewith the 1-2 link LN1-2. Accordingly, the nut 235 can perform the linearreciprocating motion without rotating in conjunction with the rotationalmotion of the shaft 231.

The second link portion LP2 includes a 2-1 link LN2-1 and a 2-2 linkLN2-2. The 2-1 LN2-1 and the 2-2 link LN2-2 of the second link portionLP2 intersect with each other in a scissor shape and are coupled to berotatable via a 1-2 hinge HG1-2.

The first link LN1 of the first link portion LP1 and the second link LN2of the second link portion LP2 are coupled to be rotatable via a secondhinge HG2. The second link LN2 of the first link portion LP1 and thefirst link LN1 of the second link portion LP2 are coupled to berotatable via a second hinge HG2. A rotation axis of the first hinge HG1and a rotation axis of the second hinge HG2 are parallel to each other.

The second hinge HG2 may be implemented as a spur gear. That is, thesecond hinge HG2 may be implemented in such a manner that a first gearG1 connected to the first link LN1 and a second gear G2 connected to thesecond link LN2 are engaged with each other. The first gear G1 and thesecond gear G2 have different rotation axes, and the rotation axes areparallel to each other. In an aspect of the disclosure, the second hingeHG2 is implemented in a form of the spur gear, so that driving stabilityand durability of the second hinge HG2 can be secured more than when thesecond hinge HG2 is implemented to have one rotation axis.

Other end of the 1-1 link LN1-1 and one end of the 2-2 link LN2-2 arecoupled to be rotatable via a 2-1 hinge HG2-1, and other end of the 1-2link LN1-2 and one end of the 2-1 link LN2-1 are coupled to be rotatablevia a 2-2 hinge HG2-2.

Other end of the 2-2 link LN2-2 is coupled to be rotatable to one end ofthe display panel 100. The one end of the display panel 100 may bedefined as an upper end of the display panel 100. The link 2-2 LN2-2 hasa degree of freedom in a rotation direction with respect to a rotationaxis extending along the third direction.

The display panel 100 may further include a head bar 600 (shown in FIG.5) at the one end of the display panel, and the other end of the 2-2link LN2-2 may be coupled to be rotatable to the head bar 600 fixed tothe one end of the display panel 100. The head bar 600 has apredetermined rigidity. When the 2-2 link LN2-2 is directly coupled tothe one end of the display panel 100, an external force due to amovement of the 2-2 link LN2-2 may be provided on the display panel 100and damage may occur. An aspect of the disclosure further includes thehead bar 600, thereby alleviating the external force that can beprovided on the display panel 100, and minimizing damage to the displaypanel 100.

The head bar 600 includes a slide rail 620. The slide rail 620 has apredetermined tracking path extending in the first direction. The sliderail 620 determines a movement path of the 2-1 link LN2-1 in the firstdirection. Other end of the 2-1 link LN2-1 is coupled to be rotatable tothe slide rail 620 and its movement is guided along the tracking path ofthe slide rail 620. The other end of the 2-1 link LN2-1 is coupled to aslider 625 to be movable along the slide rail 620 and can move along thetracking path of the slide rail 620.

The lifting unit 270 can move up and down the display panel 100 inconjunction with the linear motion from the motion converting unit 230.That is, the one end of the 1-1 link LN1-1 is coupled to the hingebracket 405 to fix the movement in the first direction, the one end ofthe 1-2 link LN1-2, which receives a driving force from the nut 235,performs a linear reciprocating motion in the first directioncorresponding to the linear reciprocating motion of the nut 235 in thefirst direction. Accordingly, in response to the linear reciprocatingmotion of the 1-2 link LN1-2 in the first direction, the one end of the1-1 link LN1-1 and the one end of the 1-2 link LN1-2 may be spaced apartfrom or adjacent to each other in the first direction. As the one end ofthe 1-1 link LN1-1 and the one end of the 1-2 link LN1-2 are disposed tobe adjacent to each other, the lift unit 270 is unfolded. On thecontrary, as the one end of the 1-1 link LN1-1 and the one end of the1-2 link LN1-2 are spaced apart, the lift unit 270 is folded. The oneend of the display panel 100 can ascend and descend in the seconddirection corresponding to a height change of the lift unit 270.

Specifically, the one end of the 1-2 link LN1-2 is moved in the +x-axisdirection in conjunction with the nut 235 moving in the +x-axisdirection ({circle around (1)}) and is disposed to be gradually adjacentto the one end of the 1-1 link LN1-1. Correspondingly, the 1-1 linkLN1-1 and the 1-2 link LN1-2 are rotated via the 1-1 hinge HG1-1, andthe other end of the 1-1 link LN1-1 and the other end of the 1-2 linkLN1-2 are disposed to be gradually adjacent to each other.Correspondingly, the one end of the 2-2 link LN2-2 coupled to the otherend of the 1-1 link LN1-1 and the one end of the 2-1 link LN2-1 coupledto the other end of the 1-2 link LN1-2 are disposed to be graduallyadjacent to each other. Correspondingly, the 2-1 link LN2-1 and the 2-2link LN2-2 are rotated via the 1-2 hinge HG1-2, and the other end of the2-1 link LN2-1 and the other end of the 2-2 link LN2-2 are disposed tobe gradually adjacent to each other. At this time, the other end of the2-1 link LN2-1 slides in the +x-axis direction along the tracking pathof the slide rail 620 and is disposed to be gradually adjacent to theother end of the 2-2 link LN2-2. Accordingly, an overall height H1 ofthe lifting unit 270 including the first link portion LP1 and the secondlink portion LP2 is increased ({circle around (2)}). The one end of thedisplay panel 100 ascends corresponding to the height of the liftingunit 270.

Conversely, the one end of the 1-2 link LN1-2 is moved in the −x-axisdirection in conjunction with the nut 235 moving in the −x-axisdirection ({circle around (1)}′) and is gradually spaced apart from theone end of the 1-1 link LN1-1. Correspondingly, the 1-1 link LN1-1 andthe 1-2 link LN1-2 are rotated via the 1-1 hinge HG1-1, and the otherend of the 1-1 link LN1-1 and the other end of the 1-2 link LN1-2 aregradually spaced apart from each other. Correspondingly, the one end ofthe 2-2 link LN2-2 coupled to the other end of the 1-1 link LN1-1 andthe one end of the 2-1 link LN2-1 coupled to the other end of the 1-2link LN1-2 are gradually spaced apart from each other. Correspondingly,the 2-1 link LN2-1 and the 2-2 link LN2-2 are rotated via the 1-2 hingeHG1-2, and the other end of the 2-1 link LN2-1 and the other end of the2-2 link LN2-2 are gradually spaced apart from each other. At this time,the other end of the 2-1 link LN2-1 slides in the −x-axis directionalong the tracking path of the slide rail 620 and is gradually spacedapart from the other end of the 2-2 link LN2-2. Accordingly, an overallheight H2 of the lifting unit 270 including the first link portion LP1and the second link portion LP2 is decreased ({circle around (2)}′). Theone end of the display panel 100 descends corresponding to the height ofthe lifting unit 270.

An aspect of the disclosure uses a driving element such as a ball screwextending in the first direction to provide a driving force for drivingthe lifting unit 270. In this instance, an area occupied by the drivingelement in the second direction can be minimized. Therefore, it ispossible to minimize the area occupied by the driving element in a statein which the lifting unit 270 is folded.

Further, an aspect of the disclosure uses a driving element such as aball screw that can convert the rotational motion of the motor 210 intoa linear motion to provide a driving force to the lifting unit 270.Accordingly, a relatively strong driving force can be generated even ina narrow space, and a load applied to the driving unit 250 can beminimized. Since it is possible to provide the driving force requiredfor the lifting unit 270 with output of the relatively small motor 210,noise and power consumption of the motor 210 for driving the liftingunit 270 can be reduced. Since the motor 210 having a relatively smallsize can be used, a compact design can be realized.

Although not shown, the lifting unit 270 may include only one linkportion LP having a first link LN1 and a second link LN2. In thisinstance, one end of the first link LN1 is coupled to be rotatable tothe hinge bracket 405, other end of the first link LN1 is coupled to berotatable to the slide rail 620 so as to be guided along the trackingpath of the slide rail 620, one end of the second link LN2 is coupled tobe rotatable so as to be linearly movable corresponding to the linearreciprocating motion of the motion converting unit 230, and other end ofthe second link LN2 may be coupled to be rotatable to one end of thedisplay panel 100.

An aspect of the disclosure can minimize a driving force required todrive the lifting unit 270 by reducing the number of link portions LPconstituting the lifting unit 270. Since the motor 210 having arelatively small size can be used, a compact design can be realized.Power consumption for driving the lifting unit 270 can be reduced, andthe relatively small motor 210 can be used, thereby realizing a compactdesign.

In addition, an aspect of the disclosure reduces the number of linkportions LP constituting the lifting unit 270 so that an area in thesecond direction occupied by the lifting unit 270 can be reduced whenthe lifting unit 270 is folded. Therefore, it is possible to reduce thearea occupied by the lifting unit 270 in a state in which the liftingunit 270 is folded.

Although not shown, one or more auxiliary link portions may be furtherprovided between the first link portion LP1 and the second link portionLP2. In this instance, the auxiliary link portion is arranged in orderalong the second direction between the first link portion LP1 and thesecond link portion LP2, and may be coupled to be rotatable to aneighboring link portion LP and/or a neighboring other auxiliary linkportion via the second hinge HG2.

The lifting unit 270 of the support assembly 200 supports the displaypanel 100 from the back side and restrains and restricts shaking andtorsion in all directions of the unrolled display panel 100. Thus, anunrolled portion of the display panel 100 can be maintained in a flatstate unless a direct physical force is applied thereto.

Referring to FIG. 12, the lifting units 270 a and 270 b may be providedon the left and right sides of the display panel 100, respectively. Thatis, an aspect of the disclosure may include a plurality of lifting units270 a and 270 b as necessary. The lifting units 270 a and 270 b may beselectively provided at appropriate positions to avoid mechanicalinterference with other structures located on the back surface of thedisplay panel 100. That is, it means that the degree of design freedomcan be improved unlike an instance when only one lifting unit 270 isprovided, the lifting unit 270 must be disposed at a center of thedisplay panel 100.

In order to drive the lifting units 270, it is necessary to provide acorresponding number of motion converting units 230. That is, in orderto drive a first lifting unit 270 a and a second lifting unit 270 b thatrespectively cover the left and right sides of the display panel 100, afirst motion converting unit 230 a and a second motion converting unit230 b may be provided, respectively.

The first motion converting unit 230 a and the second motion convertingunit 230 b may be driven by using one motor 210. In an aspect of thedisclosure, the first motion converting unit 230 a and the second motionconverting unit 230 b are driven by using one motor 210 so that thefirst lifting unit 270 a and the second lifting unit 270 b can besynchronized with each other. That is, in an aspect of the disclosure,the first motion converting unit 230 a and the second motion convertingunit 230 b are simultaneously driven by using one motor 210 so that itis possible to prevent a deviation in the moving positions of the firstlifting unit 270 a and the second lifting unit 270 b. Therefore, thereis an advantage that driving stability and product reliability of therollable display device can be secured.

A connection between the motion converting unit 230 and the motor 210may be implemented as a bevel gear BV. That is, the shafts 231 of thefirst motion converting unit 230 a and the second motion converting unit230 b can receive a driving force from the motor 210 using a structureof the bevel gear BV. Rotation axes of gears connected to the shaft 231of the first motion converting unit 230 a and the shaft 231 of thesecond motion converting unit 230 b are parallel to each other, andgears connected to the motor 210 intersect with the rotation axes of thegears connected to the shafts 231.

Since an aspect of the disclosure uses the motion converting unit 230such as a ball screw, the driving force for driving the lifting unit 270can be relatively reduced. Therefore, it is easy to drive a plurality ofmotion converting units 230 by using one motor 210.

The panel roller unit 300 may be fixed to other end of the display panel100. The other end of the display panel 100 may be defined as a lowerend of the display panel 100. The panel roller unit 300 may be rotatableabout a rotation axis extending in the first direction. Accordingly, thedisplay panel 100 can be rolled and unrolled along a periphery of thepanel roller portion 300.

The panel roller unit 300 may have a cylindrical shape. That is, across-sectional shape of the panel roller unit 300 may be circular.However, an aspect of the disclosure is not limited thereto. The panelroller unit 300 may be formed in any shape as long as the display panel100 can easily be rolled and unrolled.

The operation of rolling and unrolling the display panel 100 along theperiphery of the panel roller unit 300 can be mechanically controlled.The control operation can be implemented by the support assembly 200.That is, the display panel 100 can be rolled and unrolled along theperiphery of the panel roller unit 300 in conjunction with the foldingoperation of the lifting unit 270.

For example, when the lifting unit 270 of the support assembly 200 isunfolded, the display panel 100 is unrolled from the panel roller unit300. That is, one end of the display panel 100 rises when the liftingunit 270 is unfolded, and the display panel 100 is unrolled from thepanel roller unit 300 correspondingly. The back surface of the unrolleddisplay panel 100 is supported by the lifting unit 270 of the supportassembly 200 to maintain its flat state. Conversely, when the liftingunit 270 is folded, the display panel 100 is rolled along the peripheryof the panel roller unit 300. That is, the one end of the display panel100 is lowered when the lifting unit 270 is folded, the display panel100 is rolled along the periphery of the panel roller unit 300 inresponse thereto.

Although not shown, an aspect of the disclosure may further include atorsion spring capable of applying a predetermined tension to thedisplay panel 100 so that the display panel 100 is smoothly rolled andunrolled. The torsion spring can provide a restoring force to the panelroller unit 300 so that the panel roller unit 300 can be restored to theoriginal state.

Although not shown, the panel roller unit 300 can be driven by a drivingdevice such as a motor 210. The driving device may be a tubular motor,and may be provided in the panel roller unit 300. The driving device canconvert electrical energy into mechanical energy in synchronization witha signal from a controller, and can supply the mechanical energy to thepanel roller unit 300. The driving device may be in conjunction with thedriving unit 250 of the support assembly 200 in synchronization with acontrol signal from the controller.

An aspect of the disclosure may further include a housing 550 (shown inFIG. 5). There is an internal space for accommodating the panel rollerunit 300 inside the housing 550. The housing 550 further includes alead-in portion that opens the internal space. The display panel 100,which is rolled and unrolled to the panel roller unit 300, can be drawnin and out through the lead-in portion. A base member 510 having asupport assembly 200 may be disposed on the housing 550. The housing 550and the base member 510 may be formed as one body, but are not limitedthereto.

FIG. 13 is a view illustrating a rollable display device according toanother aspect of the disclosure.

Referring to FIG. 13A, in an aspect of the disclosure, there are twofixing points FIX1 and FIX2 at which one end of a lifting unit 270 andone end of the display panel 100 are coupled to each other. In thisinstance, one FIX1 of the fixing points FIX1 and FIX2 needs to beprovided to be slidable along a slide rail 620.

Referring to FIG. 13B, in another aspect of the disclosure, the rollabledisplay device can be implemented as a simple structure in which theslide rail 620 is removed by reducing the number of the fixing pointFIX1 at which one end of the lifting unit 270 and one end of the displaypanel 100 are coupled to each other. For example, in another aspect ofthe disclosure, the slide rail 620 can be removed by not coupling theother end of a 2-1 link LN2-1 to one end of the display panel 100 orremoving the other end of the 2-1 link LN2-1.

Another aspect of the disclosure can implement the rollable displaydevice with a simpler structure. Therefore, another aspect of thedisclosure has an advantage that a more compact design can beimplemented. Further, manufacturing cost and manufacturing time can beshortened, manufacturing defect can be reduced, and manufacturing yieldcan be improved.

FIGS. 14A and 14B are views illustrating a rollable display deviceaccording to still another aspect of the present disclosure.

Referring to FIG. 14A, when a second hinge HG2 coupling a first linkportion LP1 and a second link portion LP2 is implemented as a gear,there is a limit in folding the lifting unit 270 so that a 1-1 hingeHG1-1 of the first link portion LP1 and a 1-2 hinge HG1-2 of the secondlink portion LP2 are disposed adjacent to each other. Therefore, in afolded state of the lifting unit 270, an area D1 occupied by the liftingunit 270 in the second direction is relatively wide.

Referring to FIG. 14B, still another aspect of the disclosure ischaracterized in that links LN1 and LN2 constituting the first linkportion LP1 and/or the second link portion LP2 have a bent shape. Thebending directions of the links LN1 and LN2 constituting each linkportion LP are the same, and the bending directions of links LN1-1 andLN1-2 constituting the first link portion LP1 and links LN2-1 and LN2-2constituting the second link portion LP2 are different.

A first link LN1 and a second link LN2 may include a first portion P1and a second portion P2, respectively. The first portion P1 and thesecond portion P2 each may be a portion extending in a reverse directionwith respect to a first hinge HG1. The first portion P1 and the secondportion P2 may have a predetermined angle. That is, the first link LN1and the second link LN2 do not extend in parallel and may be bent at apredetermined angle.

For example, the 1-1 link LN1-1 and the 1-2 link LN1-2 of the first linkportion LP1 may be bent upward. In other words, the 1-1 link LN1-1 andthe 1-2 link LN1-2 of the first link portion LP1 may be bent upwardconvexly. The 2-1 link LN2-1 and the 2-2 link LN2-2 of the second linkportion LP2 may be bent downward. In other words, the 2-1 link LN2-1 andthe 2-2 link LN2-2 of the second link portion LP2 may be bent downwardconvexly.

In still another aspect of the disclosure, by bending the links LN1 andLN2 constituting the first link portion LP1 and the second link portionLP2 according to above-mentioned conditions, even when the second hingeHG2 coupling the first link portion LP1 and the second link portion LP2is implemented as a gear, the lifting unit 270 can be folded until the1-1 hinge HG1-1 of the first link portion LP1 and the 1-2 hinge HG1-2 ofthe second link portion LP2 are disposed adjacent to each other. In thisinstance, an area D2 occupied by the lifting unit 270 in the seconddirection can be minimized in the state in which the lifting unit 270 isfolded. Therefore, it is possible to minimize the area occupied by thelifting unit 270 in the state in which the lifting unit 270 is folded.

On the other hand, since the 1-1 link LN1-1 and the 1-2 link LN1-2 ofthe first link portion LP1 may be bent upward, the 1-1 link LN1-1 andthe 1-2 link LN1-2 are not arranged in parallel along the firstdirection and have a predetermined angle α in the state in which thelifting unit 270 is completely folded. Accordingly, the lifting unit 270can be smoothly unfolded by receiving a driving force in the firstdirection. That is, since the links LN1-1 and LN1-2 located at thelowermost end maintain a predetermined angle α even when the liftingunit 270 is completely folded, it can be easy to receive the drivingforce from the first direction and transmit it to the second direction.

Although aspects have been described with reference to a number ofillustrative aspects thereof, it should be understood that numerousother modifications and aspects can be devised by those skilled in theart that will fall within the scope of the principles of thisdisclosure. More particularly, various variations and modifications arepossible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A rollable display device comprising: a displaypanel; a motor generating a rotational motion; first and second motionconverting units configured to convert the rotational motion into alinear motion in a first direction and disposed at side portions,respectively, of the motor; first and second lifting units configured tomove up and down the display panel in conjunction with the linear motionof the first and second motion converting units, respectively, in asecond direction; and a bevel gear configured to connect between themotor and the motion converting units; wherein the first motionconverting unit includes: a first shaft receiving the rotational motion;and a first nut coupled to the first shaft and generating the linearmotion in the first direction corresponding a rotation direction of thefirst shaft, and wherein the second motion converting unit includes: asecond shaft receiving the rotational motion; and a second nut coupledto the second shaft and generating the linear motion in the firstdirection corresponding a rotation direction of the second shaft.
 2. Therollable display device of claim 1, wherein one end of the first shaftcoupled to a first shaft bracket, and one end of the second shaftcoupled to a second shaft bracket.
 3. The rollable display device ofclaim 2, further comprising a first bearing provided between the firstshaft and the first shaft bracket and a second bearing provided betweenthe second shaft and the second shaft bracket.
 4. The rollable displaydevice of claim 1, further comprising first and second limit sensorsconfigured to restrict a movement of the first and second nuts,respectively.
 5. The rollable display device of claim 1, wherein thefirst and second lifting units are spaced apart from each other in thefirst direction.
 6. The rollable display device of claim 1, wherein thefirst and second motion converting units to drive the first and secondlifting units, respectively.
 7. The rollable display device of claim 1,wherein the first and second motion converting units are simultaneouslydriven by using only one motor such that the first and second liftingunits are synchronized with each other.
 8. The rollable display deviceof claim 1, further comprising a head bar fixed to one end of thedisplay panel and coupled to the first and second lifting units.
 9. Arollable display device comprising: a display panel; a motor generatinga rotational motion; first and second motion converting units configuredto convert the rotational motion into a linear motion in a firstdirection and disposed at side portions, respectively, of the motor;first and second lifting units configured to move up and down thedisplay panel in conjunction with the linear motion of the first andsecond motion converting units, respectively, in a second direction; anda head bar fixed to one end of the display panel and coupled to thefirst and second lifting units, wherein the first motion converting unitincludes: a first shaft receiving the rotational motion; and a first nutcoupled to the first shaft and generating the linear motion in the firstdirection corresponding a rotation direction of the first shaft, andwherein the second motion converting unit includes: a second shaftreceiving the rotational motion; and a second nut coupled to the secondshaft and generating the linear motion in the first directioncorresponding a rotation direction of the second shaft.
 10. The rollabledisplay device of claim 9, further comprising a bevel gear configured toconnect between the motor and the first and second motion convertingunits.
 11. The rollable display device of claim 9, wherein one end ofthe first shaft coupled to a first shaft bracket, and one end of thesecond shaft coupled to a second shaft bracket.
 12. The rollable displaydevice of claim 9, further comprising a first bearing provided betweenthe first shaft and the first shaft bracket and a second bearingprovided between the second shaft and the second shaft bracket.
 13. Therollable display device of claim 9, further comprising first and secondlimit sensors configured to restrict a movement of the first and secondnuts, respectively.
 14. The rollable display device of claim 9, whereinthe first and second lifting units are spaced apart from each other inthe first direction.
 15. The rollable display device of claim 9, whereinthe first and second motion converting units drive the first and secondlifting units, respectively.
 16. The rollable display device of claim 9,wherein the first and second motion converting units are simultaneouslydriven by using only one motor such that the first and second liftingunits are synchronized with each other.
 17. The rollable display deviceof claim 1, wherein the bevel gear includes a first gear connected tothe motor, a second gear connected to the first shaft and a third gearconnected to the second shaft, and wherein a rotation axis of the firstgear intersects with rotation axes of the second and third gears, andthe rotation axes of the second and third gears are parallel to eachother.